Safety contrivance for gas-using device

Abstract

In order to safely close a shut-off device ( 2 ) used in a gas supply line ( 1 ) in the case of danger, the closing part of said shut-off device is coupled with a pneumatic working cylinder ( 4 ) whose actuating piston ( 3 ) is maintained in the respective open position of the shut-off device ( 2 ) by the accessory pressure of CO 2 liquid gas cartridge ( 5 ) and against the force of a lock spring ( 6 ). Under emergency conditions, a ventilating valve ( 8 ) which relieves the pressure form the actuating piston ( 3 ) is electronically triggered by a gas sensor ( 10 ) positioned in a sensor zone by the inactivation of a securing magnet and the shut-off device ( 2 ) is safety closed.

What is claimed is:  
     
       1. A safety device for systems using gas, comprising: 
       a gas shut-off element with a closure part, the gas shut-off element being disposed in a connecting line, the gas shut-off element having an open position and a closed position, and the gas shut-off element responding to the incorrect escape of gas by moving from the open to the closed position;  
       an operating cylinder which is arranged on the gas shut-off element and whose actuating piston is coupled mechanically to the closure part of the gas shut-off element and is held in the open position of the gas shut-off element by the pressure of a liquid-gas cartridge acting on the operating cylinder and against the force of a closing spring;  
       a vent valve, on the operating cylinder, which relieves the pressure on the actuating piston if it is moved from a blocking position to an open position, the vent valve being controlled electrically by means of a gas sensor arranged in the area to be monitored by the safety device,  
       wherein the vent valve can be moved mechanically into its blocking position and held in this position against the prevailing pressure by an electromagnet.  
     
     
       2. The safety device as claimed in  claim 1 , further comprising a linkage mechanism which converts the linear movement of the actuating piston on the side of the operating cylinder into a corresponding actuation for the gas shut-off element being selected from the group consisting of a cock and a flap. 
     
     
       3. The safety device as claimed in  claim 1 , comprising a linkage mechanism which converts the linear movement of the actuating piston on the side of the operating cylinder into a corresponding actuation for the gas shut-off element, the gas shut-off element being selected from the group consisting of a slide and a valve. 
     
     
       4. A safety device for systems using gas comprising 
       a gas shut-off element with a closure part, the gas shut-off element being disposed in a connecting line, the gas shut-off element having an open position and a closed position, and the gas shut-off element responding to the incorrect escape of gas by moving from the open to the closed position;  
       an operating cylinder which is arranged on the gas shut-off element and whose actuating piston is coupled mechanically to the closure part of the gas shut-off element and is held in the open position of the gas shut-off element by the pressure of a liquid-gas cartridge acting o n the operating cylinder and against the force of a closing spring;  
       a vent valve, on the operating cylinder, which relieves the pressure on the actuating piston if it is moved from a blocking position to an open position, the vent valve being controlled electrically by means of a gas sensor arranged in the area to be monitored by the safety device;  
       a combined switching-on mechanism by means of which, in a chronological sequence, a) the power supply for the monitoring circuit is provided, b) the vent valve is moved into its blocking position, and c) the liquid-gas cartridge on its connecting safeguard is activated.  
     
     
       5. A safety device for systems using gas comprising 
       a gas shut-off element with a closure part, the gas shut-off element being disposed in a connecting line, the gas shut-off element having an open position and a closed position, and the gas shut-off element responding to the incorrect escape of gas by moving from the open to the closed position;  
       an operating cylinder which is arranged on the gas shut-off element and whose actuating piston is coupled mechanically to the closure part of the gas shut-off element and is held in the open position of the gas shut-off element by the pressure of a liquid-gas cartridge acting on the operating cylinder and against the force of a closing spring;  
       a vent valve, on the operating cylinder, which relieves the pressure on the actuating piston if it is moved from a blocking position to an open position, the vent valve being controlled electrically by means of a gas sensor arranged in the area to be monitored by the safety device;  
       a gas sensor having a changeover contact for the explosion-proof switching-off of an electromagnet (retaining) magnet for the vent valve and for the simultaneous switching-on of an optical or acoustic warning signal.  
     
     
       6. A safety device for systems using gas comprising 
       a gas shut-off element with a closure part, the gas shut-off element being disposed in a connecting line, the gas shut-off element having an open position and a closed position, and the gas shut-off element responding to the incorrect escape of gas by moving from the open to the closed position;  
       an operating cylinder which is arranged on the gas shut-off element and whose actuating piston is coupled mechanically to the closure part of the gas shut-off element and is held in the open position of the gas shut-off element by the pressure of a liquid-gas cartridge acting on the operating cylinder and against the force of a closing spring;  
       a vent valve, on the operating cylinder, which relieves the pressure on the actuating piston if it is moved from a blocking position to an open position, the vent valve being controlled electrically by means of a gas sensor arranged in the area to be monitored by the safety device;  
       a coupling element which is capable of being pivoted and engaging in a pipeline fitting between a through valve that can be adjusted against the force of a closing spring and a bellows that is loaded in its actuating direction by a restoring spring and can be expanded by means of the filling of a liquid-gas cartridge.  
     
     
       7. The safety device as claimed in  claim 6 , further comprising 
       a coaxially displaceable valve disk which belongs to the through valve and which is mounted by its valve stem on the inner wall of the pipeline fitting by means of radial struts which permit flow and, by means of the closing spring supported on the radial struts, is pressed against a seating face arranged on the pipeline-fitting side of the through valve.  
     
     
       8. The safety device as claimed in  claim 6 , further comprising 
       an inserted connecting piece which can be fitted from the outside in an opening in the wall of the pipeline fitting, upstream of the through valve, to hold and retain the bellows acting on said through valve.  
     
     
       9. The safety device as claimed in  claim 6 , further comprising 
       a sleeve-like support element which, with a peened-over edge angled inward, engages over the actuating end of the bellows,  
       a helical compression spring that acts as a restoring force being supported opposite, on a peened-over edge angled outward, against a shoulder on the inner wall of the inserted connecting piece.  
     
     
       10. The safety device as claimed in  claim 8 , further comprising a two-armed coupling element which is pivotably mounted on the inside of the inserted connecting piece, immediately in front of the actuating end of the bellows, to act on a valve disk on the side of the through valve via a connecting pin guided concentrically within the fitting. 
     
     
       11. The safety device as claimed in  claim 6 , further comprising 
       a capillary tube connection between the liquid-gas cartridge to be interchangeably inserted into the device and the bellows functioning as the actuator for the through valve, it being possible for this pressure line to be vented by a magnetic (retaining) valve that can be triggered electrically/electronically.  
     
     
       12. A safety device for systems using gas, comprising, a gas shut-off element with a closure part, the gas shut-off element being disposed in a connecting line, the gas shut-off element having an open position and a closed position, and the gas shut-off element responding to the incorrect escape of gas by moving from the open to the closed position; 
       a pneumatic actuator which is arranged at the gas shut-off element and whose actuating element is coupled mechanically to the closure part of the gas shut-off element and is held in the open position of the gas shut-off element by the pressure of a pressure source acting on the pneumatic actuator and against the force of a restoring element;  
       a vent valve which relieves the pressure on the pneumatic actuator if it is moved from a blocking position to an open position, the vent valve being controlled electrically by means of a gas sensor arranged in the area to be monitored by the safety device, wherein the vent valve can be moved mechanically into its blocking position and held in this position against the prevailing pressure by an electromagnet.  
     
     
       13. The safety device as claimed in  claim 12 , wherein the pneumatic actuator comprises an operating cylinder with an actuating piston as actuating element. 
     
     
       14. The safety device as claimed in  claim 12 , wherein the pneumatic actuator comprises a bellows as actuating element that can be extended by means of the filling of the pressure source. 
     
     
       15. The safety device as claimed in  claim 12 , further comprising a linkage mechanism which converts a linear movement of the actuating element on the side of the pneumatic actuator into a corresponding actuation for the gas shut-off element, the gas shut-off element being selected from the group consisting of a cock, a flap, a slide and a valve. 
     
     
       16. The safety device as claimed in  claim 12 , further comprising 
       a combined switching-on mechanism by means of which, in a chronological sequence, a) the power supply for the monitoring circuit is provided, b) the vent valve is moved into its blocking position, and c) the pressure source is activated.  
     
     
       17. The safety device as claimed in  claim 12 , further comprising 
       a gas sensor having a changeover contact for the explosion-proof switching-off of an electromagnet (retaining) magnet for the vent valve and for the simultaneous switching-on of an optical or acoustic warning signal.  
     
     
       18. The safety device as claimed in  claim 12 , wherein the gas shut-off element is a through valve that can be adjusted against the force of a closing spring, the safety device comprising a coupling element which is capable of being pivoted and engaging in a pipeline fitting between the through valve and the actuating element. 
     
     
       19. The safety device as claimed in  claim 18 , further comprising a coaxially displaceable valve disk which belongs to the through valve and which is mounted by its valve stem on the inner wall of the pipeline fitting by means of radial struts which permit flow and, by means of the closing spring supported on the radial struts, is pressed against a seating face arranged on the pipeline-fitting side of the through valve. 
     
     
       20. The safety device as claimed in  claim 18 , further comprising an connecting piece which can be fitted from the outside in an opening in the wall of the pipeline fitting, upstream of the through valve, to hold and retain the pneumatic actuator acting on said through valve. 
     
     
       21. The safety device as claimed in  claim 14 , further comprising a sleeve-like support element which, with a peened-over edge angled inward, engages over the actuating end of the bellows, and a helical compression spring that acts as a restoring force being supported opposite, on a peened-over edge angled outward of the sleeve-like support element. 
     
     
       22. The safety device as claimed in  claim 21 , further comprising a two-armed coupling element which is pivotably mounted on the inside of the connecting piece, immediately in front of the actuating element, to act on a valve disk on the side of the through valve via a connecting pin guided concentrically within the fitting. 
     
     
       23. The safety device as claimed in  claim 12 , further comprising a capillary tube connection between the pressure source and the pneumatic actuator. 
     
     
       24. The safety device as claimed in  claim 12 , wherein the pressure source is a liquid-gas cartridge. 
     
     
       25. The safety device as claimed in  claim 12 , wherein the restoring element is a spring.